/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements.  See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership.  The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License.  You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
<template>
  <transition
    name="dropdown"
    @enter="setHeight"
    @after-enter="unsetHeight"
    @before-leave="setHeight"
  >
    <slot/>
  </transition>
</template>

<script>
export default {
  name: 'DropdownTransition',

  methods: {
    setHeight (items) {
      // explicitly set height so that it can be transitioned
      items.style.height = items.scrollHeight + 'px'
    },

    unsetHeight (items) {
      items.style.height = ''
    }
  }
}
</script>

<style lang="stylus">
.dropdown-enter, .dropdown-leave-to
  height 0 !important

</style>
